The Rails 5 Way, Fourth Edition

Appendix B Active Support API Reference

Active Support is a Rails library containing utility classes and extensions to Ruby’s built-in libraries. It usually doesn’t get much attention on its own—you might even call its modules the supporting cast members of the Rails ensemble.

However, Active Support’s low profile doesn’t diminish its importance in day-to-day Rails programming. To ensure that this book is useful as an offline programming companion, here is a complete, enhanced version of the Rails Active Support API reference, supplemented in many cases with realistic example usages and commentary. As you’re reviewing the material in this appendix, note that many of the methods featured here are used primarily by other Rails libraries and are ...